Personal care compositions encompass a wide variety of applications, including soaps, shampoos, skin care medicaments, cosmetics, as well as therapeutic and homeopathic skin care formulations. The use of plant-derived raw materials in personal care compositions is well established. By way of illustration, PCT patent publication WO 9913855 discloses the use of a combination of algae extract and exopolysaccharides for cosmetic and dermapharmaceutical applications.
Consideration of the use of plant-derived materials in personal care has become especially important in view of the recent discovery that certain animal-borne diseases, such as Bovine Spongiform Encephalopathy (BSE), are spread to humans through contact with infected meat and meat by-products. The sensitivity of the personal care industry to these issues is so great that even the sale of lanolin, a by-product derived from the shearing of sheep wool, has suffered because it is considered to be an animal-derived product.
The use of human-derived ingredients in personal care compositions is also frowned upon for the same reasons as suggested above for animal-derived products. Human-derived products can have even greater concerns than animal-derived constituents because pathogens borne in the human-derived cosmetic ingredients are even more likely to have a detrimental effect on human health. It has been suggested, for example, in U.S. Pat. No. 6,160,021 that human derived blood constituents, such as hemoglobin, when administered topically can influence the production of melanin in the skin providing a method of skin lightening.
As a consequence of these market pressures, personal care composition manufacturers are relying more heavily on plant-derived raw materials, such as plant proteins obtained from corn, soy and wheat replacing animal proteins. In addition, the cosmetic and personal care industries look closely to the health food and herbal supplement industries for trends in product development. Such trends are summarized, for example, in a recent article in HAPPI 38 (2001) 81. This article summarizes many of the pressures that face global cosmetic raw material manufactures and the recent trends towards ‘natural’ based products. Good examples of this are the recent trends of aromatherapy and natural extracts, particularly plant extracts, as useful ingredients for providing functionality and support the labeling claims as to such ‘natural’ based personal care products.
Several plants have enjoyed a healthy growth in personal care compositions because of their purported benefits to humans. For example, Aloe Vera is a well-known plant that provides an extract that is known to help aid wound healing. Gingo biloba and grapes are known to contain polyphenols that are purported to provide anti-oxidative effects to human skin, ameliorating the harmful effects of UV damage on the skin. Soybean extracts are extremely popular due to the presence of soy isoflavones that are suggested to contain plant phytoestrogens, compounds that mimic human estrogen and help ameliorate the effects of aging, particularly in post-menopausal women. Products such as extracts from Asafaetida and Yellow dock are suggested, for example, to minimize excess melanin formation that is responsible for the appearance of age spots on the skin. Recently, U.S. Pat. Nos. 5,371,089 and 5,602,139 disclose that plant growth regulators known as cytokinins appear to extend the longevity of human fibroblasts, the cells from which human keratinocytes arise. Keratinocytes become the protective cells that comprise the stratum corneum and make human life possible on this planet. Certain bacterial and yeast extracts are known to provide useful cosmetic, therapeutic or homeopathic effects, in particular, yeast such as Saccharomyces cerevisiae. In addition, some root extracts, for example, ginseng, have carried a historical trend for health and energy and are seen to appear in personal care products purporting such claims.
A major component of the atmosphere surrounding the earth is nitrogen gas, N2. Both plants and animals are bathed in nitrogen gas from the air and yet, because of the extraordinary chemical stability of this molecule, nitrogen gas is essentially chemically inert to both plants and animals. However, molecular nitrogen is a key component of all of the amino acids, vitamins, proteins, enzymes, and cells of both Kingdoms. Without a means for converting nitrogen gas into useful nitrogen components such as ammonia, life as we know it on this planet would not exist. The conversion of nitrogen gas into useful nitrogen substrates occurs through natural and industrial means and comprises what is known as the nitrogen cycle.
Fortunately, while plants and animals are incapable of chemically converting nitrogen into useful nitrogen-containing components, certain bacteria, especially those of the blue-green Cyanobacteria Kingdom, such as, for example, Rhizobium, have evolved a mechanism to convert nitrogen into more useful ammonia. The process of conversion is known as ‘Nitrogen Fixation’ and relies on the presence in these organisms of a key enzyme known as nitrogenase.
Nitrogen fixation is a complex enzymatic process. The general enzymatic reaction to convert nitrogen into ammonia can be summarized as:N2+8H++8e−+16ATP=2NH3+H2+16ADP+16PiThe process is intimately driven by conversion of adenosine triphosphate, ATP, into adenosine diphosphate through reduction of nitrogen to ammonia by nitrogenase enzyme. Because the reaction is a reduction reaction, it is very sensitive to the presence of oxygen.
Some free-living organisms, such as lichen, are capable of fixing nitrogen but typically on a very small scale. Interestingly, Rhizobium bacteria, however, will not convert nitrogen into ammonia when they exist alone. The bacteria are generally unable to keep the oxygen away that is detrimental to the overall nitrogen fixation reaction. In order to overcome this problem, the bacteria have evolved an unusual associative relationship with many green plants. The bacteria, which can be found readily in the soil, will infect the roots of various plants, in particular, the roots of legumes, for example. The bacteria are attracted to the roots by the excretion of various flavonoids such as luteolin and hesperetin, such flavonoids being referenced, for example, in Begum, A. A. et. al., J. Exper. Bot. 2001; 52, 1537-1543 the contents of which is incorporated in its entirety into the body of this invention.
Once within the roots of the plants, the bacteria force plants to build small, oxygen deficient homes known scientifically as symbiosomes and more commonly as ‘root nodules’ in which the bacteria can live and carry out the nitrogen fixation reaction. The plant, however, does not suffer from the infection, but instead benefits from the bacterial conversion of nitrogen into ammonia by using the ammonia for its own life processes. This relationship between the blue-green bacteria and the green plant is symbiotic. That is, both organisms benefit from the relationship. The seeds of many commercial crops that provide safe havens for nitrogen fixing bacteria are actually sold commercially with the fixing bacteria mixed with the seeds prior to planting. Such combinations can be found, for example, at commercial websites such as that provided for Agrobiologicals at http://www.agrobiologicals.com/glossary/Cont6.htm.
The bacteria build the root nodule by infecting the root hairs of the green plant and switching on the plant growth regulators that cause a rapid growth of plant cells around the infected site. The bacteria control the growth of the nodule by taking over the localized growth mechanisms of the root by using various plant growth regulators such as, for example, cytokinins as well as important complimentary plant growth regulators such as auxins, such plant growth regulators being referenced, for example in Schultze, M. et. al., Anna. Rev. Genet. 1998; 32, 33-57 incorporated in its entirety into the body of this invention. In addition, the bacteria begin expanding in size and shedding their cells walls, becoming bacteroids that begin forming a biofilm-like lining around themselves made from excreted lipopolysaccharides, exopolysaccharides and capsular polysaccharides that further prevents the infiltration of oxygen into the nodule. Such polysaccharides are referenced, for example in Rodriquez-Carvajal, M. A. et. al., Biochem. J. 2001; 357, 505-511 incorporated in is entirety into the body of this invention. Because the process of nitrogen fixation is so sensitive to the presence of oxygen and reactive oxygen radicals, the root nodule bacteria also accumulate and produce a variety of anti-oxidants including but not limited to, for example, peroxidases, superoxide dismutases, glutathiones, catalases, oxidases and other protective enzymes and molecules as might be found described in, for example, Iturbe-Ormaetxe, I. et. al., Mol. Plant. Microbe Interact. 2001; 14, 1189-1196 incorporated in its entirety into the body of this invention.
As a further defense mechanism, the bacteria begin to produce a protein known as ‘leghemoglobin’ that behaves much like human hemoglobin. The human body has four important globin molecules (distinguished by the presence of a heme-based porphyrin ring at the active site of the protein). These include myoglobin, neuroglobin, hemoglobin and a recently discovered fourth globin called histoglobin. Globin proteins are distributed throughout the human body where they capture and control oxygen reactive molecules such as O2, CO2, and NO (nitric oxide). In the symbiosomes, oxygen will bind to the leghemoglobin and is removed, through an oxygen transport mechanism, thus further improving the anaerobic conditions the bacteria require for the nitrogen fixation reaction to occur.
The interior of the nitrogen fixation nodule, therefore, is a complex mixture of plant growth regulators, amino acids, vitamins, proteins, polysaccharides, minerals and enzymes all which are either helping the plant grow, protecting or nourishing the bacteria. The composition of most of these root nodule extracts is also regionally controlled due to the soil and climates in which the individual plants are grown. However, regardless of the source of the plant, the climate or other factors, active root nodules will always contain leghemoglobin and nitrogenease.
In addition to binding oxygen, it has recently been established that globin-type proteins, such as hemoglobin, myoglobin and leghemoglobin, will bind nitric oxide (see for example, Hargrove, M et al., J. Mol. Biol. 1997; 266: 1032-1042). Nitric oxide has been found to be a potent controller of human blood flow (see, for example, Stix, G. Scientific American 2001, November). It has also become well established that an enzyme called nitric oxide synthase controls the presence of nitric oxide in the skin. Nitric oxide has been found to be part of the biochemical cascade that occurs in skin when the skin becomes irritated (see, for example, Bruch-Gerharz, D., et. al., J. Invest. Dermatol. 1998; 110:1-7). In particular, the presence of nitric oxide free radicals in the skin has been demonstrated, along with the free radicals derived from oxygen such as, for example, hydrogen peroxide, to have detrimental effects on the health of the skin (see, for example, Hurling, T. et. al., SOFW J. 2000; 126: 20-26). Accordingly, treatments to reduce nitric oxide levels on the skin have been disclosed in the literature. Illustratively, U.S. Pat. No. 6,160,021 discloses, at column 3, lines 28-45 thereof, a skin-treatment method for decreasing the level of nitric oxide by administering to the skin, either topically or subcutaneously, an inhibitor of NO synthase or an NO scavenger, such as a heme compound, such as hemoglobin.
In addition, it has recently been recognized that nitric oxide radicals appear to also be responsible for the initiation of the cascade that causes melanogenesis in human melanocytes. It has been suggested, for example, that human-derived hemoglobin can control the production of tyrosinase in fibroblasts as suggest in, for example, Romero-Graillet, C. et al., J Clin Invest., 1997; 99: 635-642, incorporated in its entirety in the body of this invention. Therefore, the control and modulation of oxygen and nitric oxide free radicals in the skin remains an area of considerable commercial and academic interest and research.
Plants can be grown and removed from the soil to expose the root nodules. Interestingly, the contents of the nitrogen fixation nodules can be extracted using various methods of extraction well known to those skilled in the art. Such examples may comprise simple aqueous extractions as, for example, discussed on the Reed College website under “Nitrogen Fixation. Part II. Physiology and Anatomy of Nitrogen Fixation” found at http://web.reed.edu/academic/department/biology/nitrogen/Nfix2.html, or they may be more complex extractions as described, for example, in Mendonca, E H M. et. al., Phytochemistry 1999; 50: 313-316. In addition, the extractions may involve the use of super critical carbon dioxide extraction, methods of which are known to those skilled in the art. These extractions will comprise a mixture of the plant growth regulators, amino acids, vitamins, proteins, polysaccharides, minerals and enzymes that comprise the root nodules.